Moisture control apparatus

ABSTRACT

A system and a method for controlling or reducing moisture levels in building cavities. Desiccant is used in combination with various containers for placing the desiccant into building cavities to control levels of moisture and mold in the cavities.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is a continuation of U.S. Non-Provisionalapplication Ser. No. 10/194,756 entitled “Method for ControllingMoisture Levels in Cavities Within Buildings,” by Shane Kretsinger,filed Jul. 12, 2002, the contents of which are hereby incorporatedherein in their entirety, which claims the benefit of U.S. ProvisionalApplication No. 60/377,687, filed May 3, 2002, the contents of which arehereby incorporated herein in their entirety; and claims the benefit ofInternational Patent Application Number PCT/US03/10548, filed Apr. 8,2003, the contents of which are hereby incorporated herein in theirentirety.

FIELD OF THE INVENTION

[0002] The present invention relates to controlling humidity. Morespecifically, the present invention relates to reducing or controllingmoisture levels in cavities within buildings.

BACKGROUND OF THE INVENTION

[0003] Moisture can accumulate in building spaces such as spaces withina wall, floor, ceiling, and fenestration cavities (the areas betweeninstalled windows or doors and the nearest framing members). There areseveral possible causes for this accumulation. Improper building designmay result in moisture entering building cavities. Structural failuresmay allow the introduction of moisture into an otherwise sound wallassembly or other structure. Such failures may include failure ofroofing materials or improper application of flashing material. Moisturebuildup in fenestration cavities can also be caused by condensation.

[0004] Moisture accumulation promotes the growth of molds and othermoisture-loving organisms. Recently, the moisture buildup and resultingmold growth in newer building cavities has become a very seriousproblem. In fact, new homes with the moist, mold-stimulating cavitiesare now so prevalent that the phenomenon has a name: Sick Home or SickBuilding Syndrome. There are over 60,000 types of known mold, andprolonged exposure to some alarmingly common types of mold can causeallergic reactions, very serious illnesses, horrific symptoms such asbleeding lungs or severe fevers, and in some cases, death. Some housesare a total loss as a result of the moisture and mold problems. Theincrease in mold-filled building cavities in new home and buildingconstruction is a source of great concern and significant speculation.

[0005] To alleviate the problem, the mold must be eliminated from thetarget building cavities or prevented from ever growing. One solution isto eliminate the moisture. Without water, mold cannot survive and willnot generate. Currently, some mechanical devices are used that circulateair through the cavities to maintain moisture levels that do not promotemold growth. These devices, however, have significant drawbacks. Forinstance, such devices are expensive and bulky, requiring costlyinstallation, continuing power costs, and valuable space. Further,installation of the mechanical devices requires the destruction ofportions of the pre-existing finish materials. In addition, thesecomplex devices will be susceptible to failures, creating furthermaintenance and repair costs and the danger that the moisture and moldmay invade a space without the owner's knowledge.

[0006] There is a need in the art for controlling moisture and moldlevels within cavities in buildings.

BRIEF SUMMARY OF THE INVENTION

[0007] The present invention, in one embodiment, is a moisture reductionapparatus having a permeable container including a desiccant that iscapable of being introduced into a building cavity. In anotherembodiment, the present invention is a composition of buildinginsulation and desiccant. In a further embodiment, the present inventionis a desiccant implant with a permeable body capable of introductioninto a wall cavity and having a cavity in the implant. In yet anotherembodiment, the present invention is a moisture control apparatus havinga permeable container, a receiver providing access to a wall assemblycavity for the permeable container, and a permeable receptacle thatreceives the permeable container.

[0008] The present invention, in another embodiment, includes a wallassembly with a wall assembly cavity, a permeable container configuredto be introduced into the cavity, and desiccant within the container.Another similar embodiment includes a wall assembly with a wall assemblycavity, a receiver providing access to the cavity, a permeable containerconfigured to be inserted through the receiver and into the cavity, anda permeable receptacle configured to enclose the permeable container.

[0009] Another embodiment of the present invention is a method ofreducing moisture that involves placing a permeable container containingdesiccant into a building cavity. The present invention, in anotherembodiment, is a method of reducing moisture including drilling a holein a finish material, inserting a permeable container including adesiccant, and filling the hole with a plug that is attached to thecontainer. A further embodiment is a method that includes drilling ahole in a finish material and inserting a permeable implant including adesiccant into the hole. An additional embodiment is a method ofreducing moisture involving providing a mixture of desiccant andbuilding insulation and inserting the mixture into a building cavity.

[0010] The present invention, in another embodiment, is a method ofcontrolling moisture that includes providing a permeable containercontaining desiccant, inserting the container into a wall assemblycavity through a receiver, and enclosing the container in a permeablereceptacle within the wall assembly cavity.

[0011] In another embodiment, the present invention is a moisturecontrol apparatus for controlling moisture within a building thatincludes a means for containing a desiccant and a means for deliveringthe desiccant to a building cavity.

[0012] While multiple embodiments are disclosed, still other embodimentsof the present invention will become apparent to those skilled in theart from the following detailed description. As will be apparent, theinvention is capable of modifications in various obvious aspects, allwithout departing from the spirit and scope of the present invention.Accordingly, the drawings and detailed description are to be regarded asillustrative in nature and not restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013]FIG. 1 is a perspective, partially sectional view of dual-stagedesiccant satchels on desiccant strips attached to the interior side ofthe exterior sheathing of a wall cavity, according to one embodiment ofthe present invention.

[0014]FIG. 2 illustrates a silica gel, according to one embodiment ofthe present invention.

[0015]FIG. 3 is a front planar view of two dual-stage desiccant satchelson a portion of a desiccant strip, according to one embodiment of thepresent invention.

[0016]FIG. 4 is a front planar view of two single-stage desiccantsatchels on a portion of a desiccant strip, according to one embodimentof the present invention.

[0017]FIG. 5 is a side elevational view of a desiccant satchel on aportion of a desiccant strip, according to one embodiment of the presentinvention.

[0018]FIG. 6 is a perspective view of dual-stage desiccant satchels ondesiccant strips attached to insulation in a wall cavity, according toone embodiment of the present invention.

[0019]FIG. 7 is a perspective view of a desiccant implant being insertedinto a hole in finish materials, according to one embodiment of thepresent invention.

[0020]FIG. 8 is a perspective view of a desiccant implant, according toone embodiment of the present invention.

[0021]FIG. 9 is a front planar view of a desiccant implant with anunattached threaded cap, according to one embodiment of the presentinvention.

[0022]FIG. 10 illustrates a mixture of desiccant comprising ten percentindicating silica gel in non-indicating silica gel.

[0023]FIG. 11 is a perspective view of desiccant and insulation beingblown into a wall cavity during new construction, according to oneembodiment of the present invention.

[0024]FIG. 12 is a perspective view of desiccant and insulation beingblown into an existing wall cavity, according to one embodiment of thepresent invention.

[0025]FIG. 13 is a perspective view of a desiccant jamb strip coupled toa jamb plug in use in a fenestration cavity, according to one embodimentof the present invention.

[0026]FIG. 14 is a front planar view of five single-stage desiccantsatchels on a desiccant jamb strip, according to one embodiment of thepresent invention.

[0027]FIG. 15 is a perspective view of five single-stage desiccantsatchels on a desiccant jamb strip coupled to a jamb plug, according toone embodiment of the present invention.

[0028]FIG. 16 is a perspective view of a wood jamb plug, according toone embodiment of the present invention.

[0029]FIG. 17 is a side elevational view of a wood jamb plug, accordingto one embodiment of the present invention.

[0030]FIG. 18 is a perspective view of a plastic jamb plug, according toone embodiment of the present invention.

[0031]FIG. 19 is a side view of a plastic jamb plug, according to oneembodiment of the present invention.

[0032]FIG. 20 is a perspective, partially sectional view of an interiorwall cavity with a plurality of barrier strips affixed to the vaporbarrier, according to one embodiment of the present invention.

[0033]FIG. 21 is front planar view of the barrier strip, according toone embodiment of the present invention.

[0034]FIG. 22 is a side elevational view of a barrier strip, accordingto one embodiment of the present invention.

[0035]FIG. 23 is a front planar view of a barrier strip having onesection partially removed, according to one embodiment of the presentinvention.

[0036]FIG. 24 is a front, partially sectional planar view of a wallcavity containing an electrical box and having a plurality of thebarrier strips affixed to a vapor barrier, according to one embodimentof the present invention.

[0037]FIG. 25 is a front partially sectional planar view of a wallcavity with a return vent and a plurality of the barrier strips affixedto the vapor barrier, according to one embodiment of the presentinvention.

[0038]FIG. 26 is front planar view of a wall cavity having a desiccantreceiver, according to one embodiment of the present invention.

[0039]FIG. 27 is a top planar view of a desiccant cartridge that isreceivable within the desiccant receiver of FIG. 26, according to oneembodiment of the present invention.

[0040]FIG. 28 is a side elevational view of the desiccant cartridge,according to one embodiment of the present invention.

[0041]FIG. 29 is a side elevational schematic illustration of thedesiccant cartridge in a flexed state, according to one embodiment ofthe present invention.

[0042]FIG. 30 is a top planar view of a removable faceplate, accordingto one embodiment of the present invention.

[0043]FIG. 31 is a front planar view of the removable faceplate,according to one embodiment of the present invention.

[0044]FIG. 32 is a side sectional view of a desiccant receiver,according to one embodiment of the present invention.

[0045]FIGS. 33A-33D illustrate a base and a cap strip, according to oneembodiment of the present invention.

[0046]FIGS. 34A-34C illustrate a base portion with an integrated tab,according to one embodiment of the present invention.

[0047]FIG. 35 illustrates a base and a cap strip installed on aninterior wall with the desiccant receiver, according to one embodimentof the present invention.

[0048]FIG. 36 illustrates a base with an integrated tab installed on aninterior wall with the desiccant receiver, according to one embodimentof the present invention.

DETAILED DESCRIPTION

[0049]FIG. 1 shows a typical wall assembly 12 with one embodiment of adesiccant strip 10 of the present invention installed to controlmoisture within a wall cavity 9. Each desiccant strip 10 is attached toa target surface 7 and has several permeable dual-stage desiccantsatchels 20 containing desiccant 22. The desiccant 22 lowers themoisture level in the wall cavity 9 by permanently adsorbing moisture.

[0050] The wall assembly 12 may be found in various types of buildingconstruction (e.g., homes, office buildings, pre-assembled homes orother pre-assembled structures, commercial buildings, trailer homes, orany other type of building where moisture removal is an issue). Such awall assembly 12 includes a frame 2 defined between a top plate 4 and abottom plate 6, with a plurality of studs 8 extending therebetween. Therectangular cavities 9 defined within the wall assembly 12 are thenenclosed on an interior side by a vapor barrier 14, which may be apolyethylene vapor barrier. Finish materials 11 such as drywall, plasteror other interior materials are then placed over the vapor barrier 14.On an opposite side of the wall assembly 12, an exterior sheathing 16 isattached and a housewrap 18 such as Tyvek (or any weather resistantbarrier) may then be placed on top of the exterior sheathing 16. Brick,siding, or some other exterior finish materials may then be placedexterior to the housewrap. Once formed, the cavities 9 become generallywater/moisture tight compartments, especially when both the vaporbarrier 14 and the housewrap 18 are utilized. This provides excellentinsulative benefits, reduces errant airflow, and also serves to furtherprotect the materials used in construction from the elements.

[0051] In most cases where the exterior sheathing 16 represents anexterior wall exposed to the elements, insulation 44 is provided in thecavities 9 between adjacent studs 8. The insulation 44 can be providedin a batt, an elongated roll, or insulating material can be blown intothe cavity 9.

[0052] One problem with making the cavity 9 restricted to airflow andgenerally moisture tight is that if moisture is introduced, it cannotescape; thus, mold growth is promoted. More and more municipalities arerequiring the use of a vapor barrier 14 and housewrap 18. Thus, thepotential for mold and moisture problems is likewise increasing.Unfortunately, a major source of moisture in cavities 9, especially innew buildings, is the lumber used to construct the wall assembly 12,such as top plates 4, bottom plates 6, and studs 8.

[0053] Lumber can absorb significant amounts of moisture prior to itsintroduction into the wall assembly 12. The kiln drying process at thelumber mill does not totally dry the lumber. During transport of thelumber to the suppliers and then to the end user, efforts to preventmoisture absorption are minimal. At the lumberyard, the lumber istypically stored outdoors under a tarp or roof at the mercy of theelements. Once the lumber reaches the jobsite, it is generally placed,uncovered, on the ground. Finally, until the roof is completed, thelumber typically continues to absorb moisture from rain, snow, or anyother source after integration into the building construction.

[0054] Thus, lumber containing a large amount of moisture is often usedto construct the wall assembly 12. After completion, as humidity levelsstabilize and the wood naturally begins to dry, this moisture isreleased into the cavity 9. Because the cavity 9 is essentially moisturetight, the released moisture remains within the cavity 9, permanentlyraising the relative humidity level. This moist environment promotesmold growth, often to an extreme.

[0055] The same phenomenon occurs in interior wall assemblies 12 inwhich neither side of the wall is an exterior wall of the building. Themoisture-tight seal in the interior wall is created by wall finishmaterials 11 such as paint or plaster. Once the seal is established,moisture released into the cavity 9 from the lumber in the wall assembly12 is trapped, permanently raising the relative humidity level and thuspromoting mold growth in the cavity 9 of the interior wall assembly 12.

I. Desiccant Strip

[0056] The desiccant strip 10 removes moisture from the wall cavity 9.The strip 10 is inserted into a wall cavity 9, where the desiccant 22 inthe satchels 20 adsorbs moisture. Moisture is a necessary ingredient formold growth. As the moisture level in the cavity 9 is reduced by thedesiccant strip 10, mold growth is prevented. With proper use, desiccantstrips 10 can prevent (or at least greatly reduce) mold growth in anybuilding cavity.

[0057] As illustrated in FIG. 1, the dual-stage satchels 20 on thedesiccant strips 10 are permeable containers. Each satchel 20 containsdesiccant 22 that captures moisture through adsorption. Adsorption isthe process of physically retaining a substance within anothersubstance. Adsorption differs from absorption because while absorptioninvolves chemical assimilation of the two substances, adsorptioninvolves only the storage of one substance within another withoutchanging the composition of either substance. The desiccant 22 adsorbsthe moisture, holding it permanently in the satchel 20. When the levelof moisture has been reduced to a certain level in the surrounding air,equilibrium capacity is reached and any additional amount of desiccantmaterial will not lower the relative humidity. Equilibrium capacity isthe level of moisture at which the unsaturated desiccant 22 cannot pullany more moisture from the air. The provided desiccant is sufficient toreduce the moisture levels to a point where mold growth is prevented.

[0058] Any material or combination of materials capable of adsorbingmoisture can be used in the desiccant satchels 20. For example, suchmaterials could include Type A silica gel (SiO₂), Type B silica gel, orany desiccant material such as: desiccant molecular sieves, Capsigels,desiccant clay, activated alumina (a highly porous form of aluminumoxide), calcium oxide (CaO), calcium sulfate (CaSO₄), and calciumchloride (CaCl₂). Silica gel 40 is depicted in FIG. 2. The terms“desiccant” or “desiccant material,” as used in this specification,shall refer to any and all materials capable of adsorbing moisture,including those listed in this paragraph, unless otherwise specified.

[0059]FIG. 3 is a front view of a portion of the desiccant strip 10. Thestrip 10 has two dual-stage satchels 20, but the length of the strip 10and the number of satchels 20 can vary depending on the desired use.Each dual-stage satchel 20 is divided into two containers: a fast-actingdesiccant container 32 and an extended duration desiccant container 34.The fast-acting desiccant container 32 holds a fast-acting desiccant 36that adsorbs moisture at a faster rate than various other desiccants.For example, the fast-acting desiccant 36 may be silica gel, as depictedin FIG. 2. An extended duration desiccant container 34 holds an extendedduration desiccant 38, e.g., calcium chloride, that adsorbs moisture ata slower rate, but for a longer period of time in comparison to variousother desiccants. Certain extended duration desiccants 38 can adsorbmoisture over a period of fifty days or more.

[0060] An alternative desiccant strip 10 depicted in FIG. 4 includes aplurality of single-stage desiccant satchels 21. Only two satchels 21are shown, but the length of the strip 10 and the number of satchels 21will vary based on the desired use and the amount of adsorptionanticipated. Some of the satchels 21 may contain fast-acting desiccant36 and others may contain extended duration desiccant 38. In oneembodiment, half of the satchels 21 on the strip 10 contain fast-actingdesiccant 36 while the other half contain extended duration desiccant38. Alternatively, all of the satchels 21 contain the same desiccant 22.

[0061]FIG. 5 is a side view of a portion of the desiccant strip 10. Thesatchel 20 includes permeable walls 24. The permeable walls 24 areconstructed of a one-way permeable material. Alternatively, thepermeable walls 24 are constructed of a two-way permeable material. Thedesiccant strip 10 has a base layer 26 that is a non-permeable backlining. The base layer 26 includes an adhesive 27 by which the desiccantstrip 10 can adhere to objects. Alternatively, any coupling mechanism ormethod known in the art can be used to attach the desiccant strip 10 toa target object.

[0062] The desiccant strip 10 includes a permeable cover layer 28opposite the base layer 26. The permeable cover layer 28 serves as anexternal cover to the satchel 20 while allowing accessibility to thesatchel 20 for moisture adsorption. That is, in selected areas andintervals, the permeable cover layer 28 forms pockets 23 that containthe satchels 20. Advantageously, the base layer 26 and the permeablecover layer 28 serve as the walls of each satchel 20. In thisembodiment, the permeable wall 24 of the satchel 20 is the permeablecover layer 28 and the opposing wall of the satchel 20 is the base layer26. Thus, desiccant 22 is accessible through one permeable cover layer28 rather than through both a permeable cover layer 28 and a permeablewall 24. A non-permeable lining 30 is removably attached to and coversthe permeable cover layer 28. The non-permeable removable lining 30protects the desiccant 22 in the satchel 20 from exposure to outside airand moisture prior to use of the desiccant strip 10. The non-permeableremovable lining 30 is intended to be removed from the desiccant strip10 within a short period of time prior to the sealing of the wall cavity9 into which the strip 10 has been placed.

[0063] The permeable cover layer 28 is a permeable plastic material. Forexample, the plastic material can be woven olefin or an uncoated,high-density polyethylene material such as Tyvek. In another aspect ofthe invention, the cover layer 28 is a fabric or a paper. Examples ofappropriate paper material include filter paper, Kraft/crepe paper, orany other permeable paper material capable of serving as the permeablecover layer 28. In embodiments in which the satchel 20 has permeablewalls 24 independent of the base layer 26 and the permeable cover layer28, the permeable walls can also be a permeable plastic material, afabric, or a paper. In one embodiment, the base layer 26 is wax paper.Alternatively, the base layer 26 may be formed using a plastic,plasticized paper or any non-permeable material that can serve as aback-lining. Alternatively, the base layer may be permeable. Thenon-permeable removable lining 30 is made of non-permeable materialsimilar to the base layer 26.

[0064] In another embodiment, the desiccant strip 10 is an adhesivestrip with adhesive on both sides. On one side, loose desiccant 22adheres to the adhesive while the adhesive on other side of the strip 10can be used to adhere the strip 10 to a target surface 7.

[0065] The desiccant strip 10 may be made by placing desiccant 22 atregular intervals between a strip of base layer 26 and a strip ofpermeable cover layer 28, joining or sandwiching the base layer 26 andpermeable cover layer 28 together to form satchels 20 of desiccant 22where the desiccant 22 was placed, and sealing the base layer 26 andpermeable cover layer 28 with a heat process to form the desiccant strip10. For example, the strip 10 can be made using an apparatus thatpositions a web of base layer 26 next to a web of permeable cover layer28, injects desiccant 22 at appropriate intervals along the length ofthe base layer 26 and cover layer 28, places the base layer 26 and coverlayer 28 in contact to form satchels 20, and then applies heat to thebase layer 26 and cover layer 28 such that the layers are sealedtogether to form the desiccant strip 10. Alternatively, the strips 10can be made by any apparatus that provides for sealing desiccant 22 intosatchels 20 at appropriate intervals along a length of a base layer 26sealed to a permeable cover layer 28. In another embodiment, thesatchels 20 are made by sealing desiccant in a permeable pouch, and thenthe satchels 20 are sealed between a strip of base layer 26 and a stripof cover layer 28. In another aspect of the present invention, the strip10 can be made by adhering loose desiccant 22 to one side of an adhesivestrip with adhesive on both sides.

[0066] In use, one or more desiccant strips 10 are placed in each of thewall cavities 9 to control the moisture level. In the case wheremoisture is introduced from the lumber used, the cavities 9 aregenerally moisture tight; thus, no additional moisture should beintroduced and the problem is permanently eliminated. In order toaccomplish the adsorption of a sufficient amount of moisture to preventsubsequent mold growth, a sufficient quantity of the desiccant material22 is provided within each wall cavity 9 to adsorb at least theanticipated level of moisture expelled from the lumber. In some cases,sufficient quantities of desiccant may be provided to adsorb more thanan anticipated level of moisture. Of course, there may be situationswhere moisture is introduced in other ways over time and as explained ingreater detail below, the present invention is useful in addressingthose issues as well.

[0067] Referring again to FIG. 1, the desiccant strips 10 are placed onthe target surface 7 within the wall cavity 9 prior to the creation ofthe airtight “envelope” of the wall cavity 9. The envelope is createdwhen the vapor barrier 14, the exterior sheathing 16, and the housewrap18 are added to the wall assembly 12, thereby sealing the wall cavity 9.Adhesive 27 on the back layer 26 of the desiccant strips 10 is used toattach the strips 10 to the target surface 7. The target surface 7 couldbe the exterior sheathing 16. Just prior to the sealing of the wallcavity 9 or installing the insulation 44, which will obscure thedesiccant strips 10 attached to the exterior sheathing 16, thenon-permeable removable lining 30 is removed from each desiccant strip10. If the wall assembly 12 is an interior wall, insulation may not benecessary, so the strips 10 may be attached to a target surface 7 andthen the wall cavity 9 may be sealed. If the wall assembly 12 is anexterior wall of the building, insulation may be inserted into thecavity 9 after the strips 10 have been attached to the target surface 7.The entire removable lining 30 is pulled from each strip 10, thusexposing the desiccant material 22 in the permeable satchels 20 to theair. Once the wall cavity 9 is sealed, the moisture released from theconstruction materials within the cavity 9 is trapped within theenvelope and the desiccant 22 in the satchels 20 begins to adsorb thetrapped moisture. Thus, moisture within the sealed cavity 9 is notallowed to reach a level where mold growth is facilitated, thuseliminating the problems associated with the presence of mold inbuilding cavities.

[0068]FIG. 6 is a perspective view illustrating the use of desiccantstrips 10 in a wall cavity 9. The desiccant strips 10 are attached tothe target surface 7, which in this case is the insulation 44 in thewall cavity 9. The strips 10 may be attached to the insulation 44 toreduce installation times (combining two steps into one) or if it isdesirable to place the insulation 44 in the wall cavity 9 prior to, orat the same time as, the placement of the strips 10. Alternatively, thetarget surface 7 is another surface such as the broad side of the studs8. The desiccant strips 10 may be attached to the insulation 44 prior tothe placement of the insulation 44 into the wall cavity 9, because thetarget surface 7 may be difficult to access after the insulation 44 hasbeen placed in the wall cavity 9. The desiccant strips 10 may even beattached to the insulation 44 prior to delivery of the insulationmaterials to the construction site, for efficiency and ease oftransportation. Alternatively, the desiccant strips 10 are attached tothe insulation 44 after delivery to the construction site but prior toplacement of the insulation 44 into the wall cavity 9, for greaterflexibility regarding the number of satchels 20 required based on thesize of the target cavities 9. In addition, the desiccant strips 10could be attached to the insulation 44 after the insulation 44 has beenplaced in the wall cavity 9.

[0069] Desiccant strips 10 are generally used in new construction. Eachstrip 10 is attached to target surfaces 7 in wall cavities 9 during theconstruction of a new building. Prior to sealing each new wall cavity 9,the non-permeable removable lining 30 is removed from each strip 10,making the desiccant 22 accessible to any moisture present in the cavity9 after it has been sealed. Alternatively, the strips 10 are used inpre-existing construction. During remodeling or other alteration of anexisting building, desiccant strips 10 are attached to target surfaces 7in newly-exposed, pre-existing wall cavities 9 or newly-added cavities 9and the removable lining 30 is removed from the strip 10 prior tosealing or re-sealing the cavity 9. Whether the wall assembly 12 is newor pre-existing, the desiccant strips 10 reduce or control the level ofmoisture in the wall cavities 9, thus providing an inexpensive andsimple system for preventing or eliminating mold growth in the wallcavities 9.

II. Desiccant Implant

[0070] The desiccant implant 50 depicted in FIG. 7 addresses moistureaccumulation and mold in pre-existing wall cavities 9. The implant 50 isfilled with desiccant 22 and inserted through a hole 66 in apre-existing wall assembly 12. Moisture within the cavity 9 is thenadsorbed by the desiccant in the implant 50. Even if a pre-existingcavity 9 is generally air tight and moisture tight as a result of theseal created by the vapor barrier 14, exterior sheathing 16, andhousewrap 18 that enclose the cavity 9, a moisture level conducive tomold growth can be trapped in the pre-existing cavity 9 when the cavity9 is first sealed during new construction and desiccant strips 10 werenot used. As explained above, the moisture may originate in the buildingmaterials, including the studs 8, used to construct the wall assembly12. Alternatively, moisture may continually accumulate in a cavity 9 asa result of some construction or structural failure or even through anintended opening (e.g., an electrical outlet) cut into the wall cavity9. The difficulty is detecting, reducing, or eliminating the level ofmoisture and the mold without extensive repair or remodeling. Removingentire sections of wall assemblies 12 in order to address moisture andmold problems in wall cavities 9 is expensive and inconvenient.Consequently, a device that helps address moisture and mold problems inwall cavities after enclosure is desirable.

[0071] The desiccant implant 50 addresses the problem of moisture andmold in pre-existing cavities 9 by allowing for moisture leveldetection, reduction, and control with a minimum of expense oralteration to the existing wall assemblies 12. The desiccant implant 50is a permeable, generally cylindrical construct that can be filled witha desiccant 22. The implant 50, containing desiccant 22, is insertedinto a pre-existing wall cavity 9 through an implant hole 66 drilledinto the wall finish materials 70.

[0072] As depicted in FIGS. 8 and 9, the implant 50 has an implantcavity 58 capable of holding desiccant 22. The desiccant can be insertedinto the cavity 58 by removing the implant cap 62, which is attached tothe implant body 60 with threads 64, and inserting the desiccant intothe body 60. The distal end 52 of the implant 50 is wedge-shaped toprovide for easy insertion into the implant hole 66. The proximal end 54of the desiccant implant 50 has a faceplate 72 with a flange 56extending beyond a diameter of the body 60 of the desiccant implant 50to prevent the implant 50 from passing entirely through the implant hole66 and falling into the wall cavity 9. The faceplate 72 can betransparent, allowing for examination of the desiccant 22.Alternatively, the faceplate 72 is opaque.

[0073] The implant 50 may be made of a plastic material. Some examplesof an appropriate plastic include polyethylene, polypropylene, or anylon. The faceplate 72 can be a transparent material, such asplexiglass or a clear plastic. In one aspect of the present invention,the plastic is oven and microwave-safe. The plastic implant 50 may bemade by an injection molding process or portions of the implant 50 maybe extruded. In another embodiment, the implant 50 is a molded ceramicmaterial, a casted metal such as aluminum, or a casted metal with aceramic coating.

[0074] The implant cavity 58 may be filled with a mixture 42 ofindicating and non-indicating desiccant as depicted in FIG. 10. Anindicating desiccant is a desiccant that indicates the amount ofmoisture it has adsorbed. A typical indicating desiccant is one thatchanges color to indicate moisture content. For example, in oneembodiment the indicating desiccant is blue when void of moisture andexhibits a gradient of color for varying levels of moisture that becomesa contrasting color such as red when the desiccant is saturated.Indicating desiccants include, but are not limited to, indicating Type Asilica gel or indicating Type B silica gel. Generally, given the higherprice of the indicating desiccants, it may be more economical to mix thetwo types of desiccants to reduce costs while using sufficient amountsof an indicating desiccant to provide the user with an indication thatmoisture is present. The mixture 42 has a ratio of indicating desiccantto non-indicating desiccant material of 1:10. Alternatively, the ratiocan be any ratio that allows both adsorption and indication. In analternate embodiment, the implant cavity 58 can be filled entirely withan indicating or non-indicating desiccant material. In another aspect ofthe invention, the implant cavity 58 can be filled with some materialfor testing for the presence of mold. Alternatively, the material is anytype of media indicator.

[0075] The size of the implant 50 can be varied as desired. For example,with wall cavities with 2×4 studs 8, the implant 50 may have a diameterof 1.5 inches and a length of 3.5 inches. For wall cavities with 2×6studs or larger, the implant can have a length of 5.5 inches. Further,the implant 50 can be filled with desiccant 22, or, alternatively, thedesiccant 22 is first placed into a permeable container (not shown) andthen the permeable container is inserted into the implant cavity 58. Inaddition to threads, the implant cap 62 can be attached to the implantbody 60 by any attachment mechanism, such as snaps, clips, or fasteners.The distal end 52 as depicted in FIG. 7 as wedge-shaped, but analternate embodiment is a rounded distal end (not shown). The distal end52 could have any shape that assists in or promotes the insertion of theimplant 50 as described below.

[0076] Returning to FIG. 7, the implant can be inserted into the wallcavity 9 from the exterior side (not shown) of the wall assembly 12through an implant hole 66 drilled in exterior wall finish materials.For insertion from the exterior side, the exterior finish materials maybe removed or simply lifted in a desirable location, the housewrap 18opened or lifted, and an implant hole 66 drilled into the cavity 9. Thehole 66 may also be drilled directly through the exterior finishmaterials, the housewrap 18, and the exterior sheathing 16.Alternatively, the implant is inserted from the interior side 11 throughan implant hole 66 drilled in interior finish materials 11.

[0077] Once the implant 50 is in the implant hole 66, the desiccant 22in the implant 50 adsorbs moisture in the cavity 9. Due to its smallsize and method of use, the implant 50 can remove problem moisturewithout damaging large amounts of the pre-existing construction. Thatis, the moisture levels in a pre-existing cavity 9 can be successfullyreduced or eliminated by simply drilling a small hole 66 in aninconspicuous location in the wall finish materials 70 and inserting theimplant 50 into the hole 66. After use, the hole can easily be repairedor the implant 50 can remain in place, either being covered over, orhaving a suitable appearance to remain uncovered. The desiccant implant50 filled with desiccant 22 may be reusable. More particularly, thedesiccant itself may be processed to void the moisture from thedesiccant 22. Moisture can be removed from desiccant 22 by applying heatto the desiccant 22. The desiccant 22 is removed from the implant 50 andthe moisture is baked out of the desiccant 22. The moisture is removedby baking the desiccant 22 in a conventional oven, or alternatively, byplacing the desiccant 22 in a microwave oven. Alternatively, thesaturated desiccant 22 is left in the desiccant implant 50 and themoisture is removed from the desiccant 22 by applying heat to theimplant 50. The desiccant implant 50 filled with saturated desiccant 22is placed in a conventional oven or alternatively in a microwave oven tovoid the desiccant 22 of moisture.

[0078] The implant 50 can be used for moisture detection. As depicted inFIG. 7, the implant 50 is introduced into the implant hole 66 and leftin position for a pre-determined period of time before being removed.Once the pre-determined period of time has passed, the implant 50 isremoved from the hole 66. After removal, the desiccant 22 in the implant50 is examined to determine the level of moisture in the wall cavity 9.Alternatively, the indicating desiccant can be examined through thetransparent faceplate 72 without having to remove the implant 50 fromthe hole 66. The amount of moisture present is determined by the type ofindicating desiccant used and the amount of color change (or other typeof indication) over the pre-determined period of time. If the indicatingdesiccant in the implant 50 has not changed color, the wall cavity 9contains little or no moisture. If the indicating desiccant has changedcolor, the amount of change and rate of speed of the change can indicatethe level of moisture in the wall cavity 9.

[0079] The implant 50 can be used for moisture reduction or elimination.Moisture reduction may be desirable because the moisture level is knownto be at an undesirable level or because a previously-inserted implant50 indicated as much. The implant 50, filled with a desiccant 22, isinserted into the implant hole 66. Upon saturation, the implant 50 isremoved, voided of moisture, and re-inserted into the implant hole 66.Alternatively, another implant 50 with desiccant 22 is inserted in itsplace. In a further alternative, more implant holes 66 are drilled intothe wall cavity 9 and more implants 50 are inserted into the cavity 9.The re-insertion or replacement of the implant 50 at pre-determinedintervals continues until the moisture level has reached a desired levelor equilibrium capacity. Alternatively, the repeated use and saturationof the implant 50 may indicate that there is a failure in theconstruction or other problem allowing moisture into the target cavity9, thus indicating that the construction failure or problem must becorrected before the moisture problem can be resolved.

[0080] Several factors may be considered in determining thepre-determined period of time that an implant 50 remains in the implanthole 66 for moisture detection. The type of indicating desiccant, thepercentage of indicating desiccant in a mixture with non-indicatingdesiccant, or the size of the implant can impact the rate and extentthat the desiccant or mixture changes color or otherwise indicates thepresence of moisture. The amount of moisture anticipated to be presentin the wall cavity 9 and the type of wall cavity 9 are factors. If it isexpected that the wall cavity 9 has a high moisture content, thepre-determined time before removal may be shorter than if it isanticipated that the wall cavity 9 is relatively dry.

[0081] The desiccant implant 50 could be placed permanently into thewall finish materials 70 and wall cavity 9. The implant 50 is filledwith an extended duration desiccant 22 that is permanently affixed inthe implant hole 66. The implant 50 is permanently affixed using along-lasting glue or sealant 68. Alternatively, the implant 50 ispermanently affixed using some attachment apparatus such as nails, ortacks.

[0082] The flange 56 on the implant 50 may have a sealing compound orsimilar sealant 68 to create a seal between the flange 56 and the finishmaterials 11. The resulting seal prevents air and moisture from enteringthe wall cavity 6 through any space between the desiccant implant 50 andthe wall finish materials 11.

III. Insulation/Desiccant Mixture

[0083] A mixture of loose insulation and desiccant is also provided foruse in cavities 9. The desiccant mixture 80 can be blown into a cavity,thus providing desiccant to adsorb any moisture within the cavity.

[0084]FIG. 11 is a perspective view of a mixture 80 of loose insulationand desiccant being blown into a wall cavity 9 in new construction. Anydesiccant material or combination of desiccant materials capable ofadsorbing moisture can be used in the insulation/desiccant mixture 80.The insulation/desiccant mixture 80 can be created quickly andefficiently, simply mixing the desired ratio of insulation and desiccantand blowing it into the cavity 9. For efficiency and ease oftransportation, the insulation/desiccant mixture 80 may be created priorto delivery of the insulation to the construction site. Alternatively,the insulation/desiccant mixture 80 is created after delivery of theinsulation to the construction site in order to provide flexibility;i.e., the ratio of insulation to desiccant can be changed based on theconditions for use.

[0085] In use, an insulation/desiccant mixture 80 is generally blowninto a wall cavity 9 or other type of cavity, such as in or around aroof. The mixture 80 is placed into an insulation blowing machine 82. Ahose 84 attached to the insulation blowing machine 82 can be used todirect the insulation/desiccant mixture 80 into the desired areas of thewall cavity 9 of new construction prior to sealing the structuralcavity. Once the wall cavity 9 has been sealed, the desiccant in themixture 80 adsorbs moisture, thus reducing the level of moisture presentin the cavity 9 and therefore reducing the presence of mold in thecavity 9.

[0086] As illustrated in FIG. 12, the insulation/desiccant mixture 80can be blown into a wall cavity 9 in pre-existing construction. Themixture 80 is placed into an insulation blowing machine 80 and directedinto a wall cavity 9 through a hose 84 attached to the insulationblowing machine. For pre-existing construction, an access hole 86 isbored into the pre-existing structural finish materials to provideaccess to the wall cavity 9. The insulation/desiccant mixture 80 isblown into the target cavity by inserting the hose 84 into the accesshole 86. Access holes 86 may be bored into the pre-existing structuralfinish material to coincide to each cavity created by the structuralsupports such as wall studs, and the mixture 80 is blown into eachcavity 9. After the cavities 9 have been filled with the mixture 80, theaccess holes 86 are plugged or closed.

IV. Insulation/Desiccant Structure

[0087] According to another embodiment, an insulation/desiccantstructure is provided for use in wall cavities 9. Any desiccant 22 orcombination of desiccants 22 capable of adsorbing moisture can be usedin the insulation/desiccant structure. The apparatus is created byintegrating desiccant 22 into a common insulation roll or batt. Aninsulation roll or batt is a strip of insulation which may have a paperbacking. In use, the insulation/desiccant structure is inserted into thewall cavity 9 prior to sealing the cavity 9 closed. The desiccant 22 inthe structure is capable of adsorbing moisture present inside the wallcavity 9. Alternatively, the desiccant 22 can be integrated into thepaper backing on the insulation batt or roll.

V. Desiccant Package

[0088] An alternate aspect of the invention is a desiccant package: apackage of desiccant material for controlling moisture levels inbuilding cavities 9. The desiccant package (not shown) is placed insidethe building cavity 9. Alternatively, the package may be hung orotherwise affixed inside the building cavity 9. The desiccant packagemay be a cloth bag containing desiccant. Alternatively, the desiccantpackage is any permeable packaging material capable of permittingmoisture access to the desiccant included therein, including cardboard,plastic, metal, etc. The package, furthermore, can be a box, canister,or any other container capable of holding substantial amounts ofdesiccant. In some embodiments, several desiccant packages may be placedin a cavity 9.

VI. Desiccant Jamb Strip and Jamb Plug

[0089] For some building and wall cavities 9, a desiccant jamb strip 90and jamb plug 112 as depicted in FIG. 13 may be used. A jamb strip 90can be inserted through a hole into a fenestration cavity 124 or wallcavity 9 and hung from a plug 112 inserted into the hole. Desiccant 22within the jamb strip 90 adsorbs moisture within the cavity.

[0090] Fenestration cavities 124 present a different situation thanother types of building cavities 9. The fenestration cavities 124 aresmaller and relatively more inaccessible than wall or other buildingcavities 9. Yet, as with more accessible cavities 9, fenestrationcavities 124, door cavities (not shown), and other inaccessible cavitiesmay have moisture levels conducive to mold growth. Due to the limitedaccess, moisture in a fenestration cavity 124 or other relativelyinaccessible cavity 9 can be removed by boring a minimal number of jambstrip holes 118 into the cavity 124 (preferably only one hole in someinstances) and inserting a substantial amount of desiccant in jamb strip90 form. The jamb strip 90 can be varied in length and amount ofdesiccant, and can be inserted through a single hole 118 and hung insidethe target cavity 124.

[0091]FIG. 14 is a front view of a desiccant jamb strip 90. The jambstrip 90 includes five desiccant jamb satchels 92. The number ofsatchels 92 in a jamb strip can vary depending on desired length or thenumber of satchels 92 that the target cavity 9 is capable of holding.Each jamb satchel 92 is a permeable container containing desiccant 22accessible to moisture in the surrounding air. As previously described,each satchel 92 can contain any desiccant 22 or mixture of desiccants22, including indicating desiccants. The jamb strip 90 may include anon-permeable removable lining (not shown) attached to the satchels 92and intended to make the desiccant inaccessible to the air until removalof the lining just prior to insertion of the jamb strip 90 into a targetcavity 9.

[0092] The satchels 92 are made of a permeable plastic material. Forexample, the plastic material can be woven olefin or an uncoated,high-density polyethylene material such as Tyvek. In another aspect ofthe invention, the satchel 28 is a fabric or a paper. Examples ofappropriate paper material include filter paper, Kraft/crepe paper, orany other permeable paper material capable of serving as the permeablecover layer 28. In embodiments in which the desiccant 22 is enclosedbetween two strips of plastic, at least one sheet is also a permeableplastic material, a fabric, or a paper. Alternatively, one strip is waxpaper. In another aspect, one strip is a plastic, plasticized paper, orany non-permeable material that can serve as a lining.

[0093] According to one embodiment, the jamb strip 90 is made in afashion similar to the desiccant strip 10. Desiccant 22 is placed atregular intervals between two strips of plastic, at least one of whichis permeable. The two strips of plastic are joined or sandwichedtogether to form satchels 92 of desiccant 22 where the desiccant 22 wasplaced. The two strips are then sealed together with a heat process toform the desiccant jamb strip 90. Alternatively, the strips 90 can bemade by any apparatus that provides for sealing desiccant 22 intosatchels 92 at appropriate intervals between two strips of plastic. Inanother embodiment, the satchels 92 are made by sealing desiccant in apermeable pouch, and then the satchels 20 are sealed between two stripsof plastic.

[0094] The jamb strip 90 attaches to a jamb plug 112 as depicted in FIG.15. The jamb plug 112 is a generally cylindrical body. Alternatively,the plug 112 is any shape desirable to fill the hole 118 created forinsertion of the jamb strip 90. The desiccant jamb strip 90 is connectedto the jamb plug 112 via a string member 114 between the jamb strip 90and the plug 112. The string member 114 may be, for example, a string,cord, cable, or any other length of material for connecting objects. Thestring member 114 is connected to a jamb hook 116 that is coupled withthe jamb plug 112 or alternatively by a clip, an eyelet, or a clamp. Thejamb hook 116 is located on the distal end 117 of the jamb plug 112. Thestring member 114 may be removable from the jamb hook 116.

[0095] The jamb plug 112 may be a wood jamb plug 100 as depicted inFIGS. 16 and 17. The jamb plug 100 has an attachment tang 102 extendingfrom the distal end X of the plug 100. The desiccant jamb strip 90attaches to the jamb plug 100 at the attachment tang 102. Alternatively,the jamb plug 112 may be a plastic jamb plug 104 as depicted in FIGS. 19and 20. The jamb plug 104 has attachment tabs 106 extending from thedistal end of the plug 104. The attachment tabs 106 expandcircumferentially to hold the jamb plug 104 upon insertion into thestrip hole 118. The desiccant jamb strip 90 attaches to the jamb plug104 at an attachment hook 108 extending from the distal end of the plug104. In one aspect of the present invention, the desiccant jamb strip 90is detachable from the jamb plug 112.

[0096] Returning to FIG. 13, a jamb strip hole 118 is drilled into anextension jamb 120. Alternatively, the hole 118 is drilled into thewindow body 122, a door body, or any other building structure with acavity. The desiccant jamb strip 90 is inserted into the targetfenestration cavity 124 through the strip hole 118 and hangs from thejamb plug 112. The jamb plug 112 fits snugly into and covers the hole118 while suspending the jamb strip 110 in the fenestration cavity 124.Upon plugging the hole 118 with the jamb plug 112, the desiccant 22 inthe jamb satchels 92 begins to adsorb the moisture present in thefenestration cavity 124, thus reducing or eliminating any moisturepresent in the cavity 124.

[0097] The desiccant jamb strip 90 attached to the plug 112 is reusable.The jamb strip 90 and plug 112 can be removed from the cavity 124 andheated to void the desiccant 22 of moisture. After voiding, the jambstrip 90 and plug 112 are again placed into their previous position.Alternatively, the jamb strip 90 is examined upon removal from thecavity 124 to determine the level of moisture in the cavity 124. If thedesiccant 22 in the strip 90 indicates saturation of the desiccant 22 orsome moisture level that requires further adsorption, the strip 90 isheated to void the moisture and the strip 90 and plug 112 are reinsertedinto the cavity 124. If the desiccant 22 indicates a desired low levelof moisture or equilibrium capacity, the strip 90 is voided of moistureand the strip 90 and plug 112 are permanently re-inserted into thecavity 124. Alternatively, if the desired level of moisture is reached,the strip hole 118 may be permanently covered or sealed.

VII. Desiccant Barrier Strip

[0098] Referring to FIG. 20, another cavity, the barrier cavity 198,exists between the installed vapor barrier 14 and the drywall 11(representative of any finish material). A desiccant barrier strip 200containing desiccant 22 can be inserted into the barrier cavity 198. Thedesiccant 22 within the strip 200 adsorbs moisture, thus reducing themoisture level within the barrier cavity 198.

[0099] Because the drywall 11 is often painted or covered, it alsobecomes impermeable to moisture, allowing moisture within the barriercavity 198 to become trapped. Thus, any moisture that is trapped withinthis barrier cavity 198 has a tendency to condense on the vapor barrier14 and run towards the base plate (or sill plate) 6. Therefore, it iscommon to see mold growth near the bottom portions of walls due to thisphenomenon. In addition to moisture that may be trapped within thebarrier cavity 198 from construction, moisture may be introduced intothe barrier cavity 198 through any openings, such as an outlet 196, thatare cut through the drywall 11. Moisture from the room may enter thebarrier cavity 198 through any such opening, effectively become trappedwithin, and either condense on the vapor barrier 14 or raise thehumidity level within the wall cavity 9, lending to an environmentconducive to mold growth.

[0100] While the wall cavity desiccant strips 10 are effective atremoving moisture from the wall cavity 9, they will have no effect onthe barrier cavity 198 between the vapor barrier 14 and the drywall 11,because the wall cavity 9 and the barrier cavity 198 are separated by amoisture tight seal created by the vapor barrier 14. Thus, prior toinstalling the drywall 11, one or more desiccant barrier strips 200 canbe applied to the vapor barrier 14. The barrier strips 200 are similarto the desiccant strips 200 in that they contain one or more types ofdesiccant material to permanently remove moisture from their exposedsurroundings.

[0101]FIG. 21 illustrates barrier strip 200 as a non-permeable cover 206is being removed to expose each desiccant satchel 204 containingdesiccant. FIG. 22 illustrates the general construction of the barrierstrip 200. The barrier strip 200 includes a non-permeable base layer208, to which a layer of adhesive 212 is applied. An adhesive cover 210is provided to protect the adhesive layer 212 until the barrier strip200 is to be applied to the vapor barrier 14. A desiccant satchel 204 isprovided having permeable walls 205 and containing one or more desiccantmaterials (not shown). The desiccant satchel 204 is formed from amoisture permeable material so that ambient moisture can be adsorbed.The satchel 204 is covered by a permeable cover layer 207 to support thesatchel 204 on the strip 200. Alternatively, the permeable cover layer207 forms a permeable wall 205 of the satchel 204 while thenon-permeable base layer 208 forms another wall 205 of the satchel 204.To protect the desiccant satchel 204 from exposure prior to its intendeduse, a removable, non-permeable cover 206 is provided.

[0102]FIG. 23 illustrates that barrier strip 200 is formed from aplurality of individual satchel packets 201, 202, 203 to form anydesired length. Generally, the barrier strip 200 will be provided inbulk and sections will be torn off to form a desired length. Theadhesive backing 210 is removed and the barrier strip is then affixed tothe vapor barrier 14 in the appropriate locations. Just prior tocovering the vapor barrier 14, the cover 206 is removed so that moisturecan be adsorbed.

[0103] As with the desiccant strip 10, the permeable cover layer 207 ofthe barrier strip 200 is a permeable plastic material. For example, theplastic material can be woven olefin or an uncoated, high-densitypolyethylene material such as Tyvek. In another aspect of the invention,the cover layer 207 is a fabric or a paper. Examples of appropriatepaper material include filter paper, Kraft/crepe paper, or any otherpermeable paper material capable of serving as the permeable cover layer207. In embodiments in which the satchel 204 has permeable walls 205independent of the base layer 208 and the permeable cover layer 207, thepermeable walls 205 can also be a permeable plastic material, a fabric,or a paper. The base layer 208 is wax paper. Alternatively, the baselayer 208 is a plastic or plasticized paper. In a further alternative,the base layer 208 is any non-permeable material that can serve as aback-lining. The non-permeable cover 206 is made of material similar tothe base layer 26.

[0104] According to one embodiment, the barrier strip 200 is made byplacing desiccant 22 at regular intervals between a strip of base layer208 and a strip of permeable cover layer 207, joining or sandwiching thebase layer 208 and permeable cover layer 207 together to form satchels204 of desiccant 22 where the desiccant 22 was placed, and sealing thebase layer 208 and permeable cover layer 207 with a heat process to formthe desiccant strip 200. For example, the strip 200 can be made using anapparatus that positions a strip of base layer 208 next to a strip ofpermeable cover layer 207, injects desiccant 22 at appropriate intervalsalong the length of the base layer 208 and cover layer 207, places thebase layer 208 and cover layer 207 in contact to form satchels 204, andthen applying heat to the base layer 208 and cover layer 207 such thatthe layers are sealed together to form the desiccant strip 200.Alternatively, the strips 200 can be made by any apparatus that providesfor sealing desiccant 22 into satchels 204 at appropriate intervalsalong a length of a base layer 208 sealed to a permeable cover layer207. In another embodiment, the satchels 204 are made by sealingdesiccant 22 in a pouch with permeable walls 205, and then the satchels204 are sealed between a strip of base layer 208 and a strip of coverlayer 207.

[0105] As illustrated in FIG. 20, barrier strips 200 can be placed inthe lower portion of the vapor barrier 14 in each wall cavity 9 toabsorb the moisture that condenses and runs down the vapor barrier 14.In addition, barrier strips can be placed in any desired location andany location where mold is traditionally problematic. For example, moldoften tends to accumulate near the upper corners of walls in bathrooms.Thus, the barrier strips 200 can be added there. As noted above,openings in the drywall 11 or finish materials may lead to theintroduction of moisture. Thus, the barrier strips 200 can be added tothese locations. FIG. 24 illustrates a plurality of barrier strips 200surrounding an installed electrical box 220, that creates an openingthrough the drywall 11. Similarly, FIG. 25 illustrates an air vent 222having barrier strips 200 affixed above and below the vent 222.Generally, the barrier strips are attached to the vapor barrier 14;however, they could be attached to the rear surface of the drywall 11 orany other finish material. This may make the installation of the drywall11 more complex if the barrier strips 200 align with a stud 8, as thiswill result in an increased gap.

[0106] The barrier strips 200 and the desiccant strips 10 are ideal foradsorbing moisture trapped within a compartment. As noted above,however, there may be situations where airflow is permitted into a givencompartment and moisture can be introduced over time. The desiccantspike 50 and jamb strip 90 discussed above offer one way to address thismoisture; that is to test for its presence and/or remove the moisture.

VIII. Receiver

[0107]FIG. 26 illustrates a receiver 250 that will allow desiccant to beeasily replenished within wall cavities on a maintenance schedule. Thiscan be done as a preventative measure to address moisture that mightaccumulate or can be used when moisture is known to be a problem.

[0108] The receiver 250 is installed where a base or molding can be usedas a cover, thus the receiver 250 is preferably installed at the top orthe bottom of the wall cavity 9. As not all construction will include acrown molding and crown molding is more difficult to work with, theeasiest installation is at the bottom of the wall cavity 9. The receiver250 is anchored to the adjacent studs 8 and to the bottom plate 6. Thereceiver 250 can be made from a material such as nylon so that screws,nails or other fasteners can be utilized without fracturing the receiver250. As illustrated, the receiver 250 is a modular component andincludes a cavity desiccant receiver 252 and a barrier desiccantreceiver 254. The cavity desiccant receiver 252 is coupled to a flexiblemesh receiving stocking 262 disposed within the wall cavity 9 andanchored to a suspension bar 264 disposed between adjoining studs 8. Thestocking 262 is a receptacle that could just as easily be a rigid,permeable component. As will be described in greater detail, a desiccantcartridge can be inserted through an opening behind cavity receiverfaceplate 256. Thus, desiccant can easily be replaced within the wallcavity 9. Similarly, desiccant is inserted through an opening behindbarrier faceplate 258. Thus, desiccant is replaceably introduced intothe gap between the vapor barrier 14 and the finish materials 11.

[0109]FIGS. 27-29 illustrate one embodiment of a desiccant cartridge 270that can be introduced through the opening behind cavity receiverfaceplate 256. The desiccant cartridge contains a supply of one or moretypes of desiccant and could include an indicating desiccant to indicatethe presence of moisture. The supply of desiccant can either bereplaced, moisture can be removed by heating, or an entirely newcartridge 270 can be used. As the cartridge 270 is inserted, it isflexible and conforms to the receiving stocking 262 as indicated in FIG.29. Though not shown, the receiving stocking is located within theinsulation and serves to guide the cartridge 270 so as not to damage ordisplace the insulation.

[0110]FIGS. 30 and 31 illustrate one embodiment of cavity receiverfaceplate 256. Locking tabs 280 can be provided to selectively securethe plate in place. A relief tang 282 can be provided to provide agripping point for finger or a tool such as pliers so that the faceplate256 can be easily removed.

[0111]FIG. 32 is a side, sectional view illustrating that barrierreceiver 252 is located between the vapor barrier 14 and the drywall 11.A barrier desiccant satchel 300 containing a quantity of desiccant isselectively and replaceably placed within the barrier receiver 252 andadsorbs moisture from the barrier cavity 198. After a predeterminedperiod of time, the satchel 300 is removed. The desiccant within may bereplaced, recharged through heating or a new satchel may be used. In anyevent, a satchel with active desiccant is replaced within the barrierreceiver 252.

[0112]FIG. 33A more clearly illustrates the position of the receiver 250with respect to the wall components. The vapor barrier 14 is sandwichedbetween the barrier receiver 254 and the cavity receiver 252, thusholding the vapor barrier 14 in place. This also illustrates how barrierreceiver 254 gains access to the barrier cavity 198 while the cavityreceiver 252 gains access to the wall cavity 9.

[0113] Once installed, the receiver 250 allows desiccant material to beroutinely replaced within the wall cavity 9 or the barrier cavity 198.However, the receiver 250 itself may be unsightly or inappropriate forfinished construction. Thus, it may be desirable to cover the receiver250 with a more attractive finished product. As stated above, thereceiver 250 is sized to coincide with various base moldings (or crownmoldings if used in an upper part of a wall). FIGS. 33A-33D illustratehow a traditional wooden molding (or other solid material) can be usedwith receiver 250. A cap strip 310 is nailed or otherwise affixed to thedrywall 11. The wooden molding is a base 312 that has an upper surfacethat engages the cap strip so that the base 312 is held flush to thedrywall 11. Additionally, and optionally a hook and loop type fastener316 can be applied to a rear surface 314 of base 312 to further serve toaffix the base 312 to the receiver 250. Of course, any type or style ofbase or mold could be utilized to cover receiver 250 and any type offastening device or system could be employed so long as access to thereceiver 250 is permitted.

[0114] In many commercial construction applications, a rubber orflexible cover base 320 is used as illustrated in FIGS. 34A-34C. Thecover base 320 can also be used to obscure the receiver 250 by providinga bead 322 along a rear surface that engages a groove 324 provided inthe receiver 250. The cover base 322 is pressed against the receiver 250and the bead 322 snaps into the groove 324 to hold the cover base 322 inplace.

[0115]FIG. 35 illustrates the receivers 250 in place and illustrates howa separate receiver 250 is used for each wall cavity 9. The receivers250 abut one another to form a continuous line. The wood base 312 isillustrated to show how it covers and obscures the receivers 250. Thedrywall 11 is shortened by the receivers 250 because the drywall 11rests on top of, and flush with, the receivers 250. FIG. 36 is a similarview illustrating the use of the cover base 322 to obscure the receivers250.

[0116] Another embodiment of the present invention for controlling themoisture in the barrier cavity 198 is a drywall desiccant apparatus forcontrolling moisture levels. Any desiccant material or combination ofdesiccant materials capable of adsorbing moisture can be used in thedrywall desiccant apparatus. Desiccant 22 is integrated into a sheet ofdrywall 11, which is then placed onto the wall assembly 12, making thebarrier cavity 198 moisture-tight. The moisture-tight seal traps anyexisting moisture in the cavity 198. The desiccant 22 in the drywall 11reduces the moisture level in the cavity 198 by adsorbing the moisture.Alternatively, a desiccant paper capable of adsorbing moisture presentin the barrier cavity 198 can be placed on a side of the drywall 11inside the barrier cavity 198.

[0117] The various desiccant delivery systems described herein can beused in any number of construction and remedial applications, for bothresidential and commercial construction. They may be used in new homeand building construction to prevent problems associated with thedispersion of moisture from building materials; they may be used as aremedial measure to address a moisture problem in an existing structure;or they may be installed to permit desiccant to be exchanged on aperiodic basis. The desiccant delivery systems can be used in newconstruction, pre-assembled homes or other pre-assembled structures,commercial buildings, trailer homes, or any other type of building wheremoisture removal is an issue.

[0118] Although the present invention has been described with referenceto preferred embodiments, persons skilled in the art will recognize thatchanges may be made in form and detail without departing from the spiritand scope of the invention.

What is claimed is:
 1. A desiccant implant comprising: a permeable bodyfor insertion into a wall cavity; and a cavity within the permeablebody.
 2. The implant of claim 1 further comprising a removable cap at adistal end of the implant.
 3. The implant of claim 1 further comprisinga flange at a proximal end of the implant such that the flange has adiameter greater than a diameter of the permeable body.
 4. The implantof claim 3 wherein the flange has a sealant member on a side facing adistal end of the implant.
 5. The implant of claim 1 wherein the cavityis filled with a desiccant.
 6. The implant of claim 5 wherein thedesiccant is a mixture of an indicating desiccant and a non-indicatingdesiccant.
 7. The implant of claim 5 wherein the desiccant is a mixtureof a fast-acting desiccant and an extended duration desiccant.
 8. Theimplant of claim 1 wherein the cavity is filled with a media indicator.9. The implant of claim 1 further comprising a rounded distal end. 10.The implant of claim 1 further comprising a wedge-shaped distal end. 11.The implant of claim 1 further comprising a transparent faceplate at aproximal end of the implant.
 12. A moisture control apparatuscomprising: a first receiver providing access to a first wall assemblycavity, the first receiver configured to receive a first desiccant; afirst permeable receptacle coupled to the first receiver, the firstpermeable receptacle configured to enclose the first desiccant; and asecond receiver providing access to a second wall assembly cavity, thesecond receiver being adjacent to the first receiver and configured toreceive a second desiccant.
 13. The moisture control apparatus of claim12 wherein the first wall assembly cavity is a wall cavity and thesecond wall assembly cavity is a barrier cavity.
 14. A wall assemblycomprising: a wall assembly cavity; a receiver providing access to thewall assembly cavity; a permeable container configured to be insertedthrough the receiver and into the wall assembly cavity; and a permeablereceptacle coupled with the receiver, the permeable receptacleconfigured to enclose the permeable container.
 15. The wall assembly ofclaim 14 wherein the wall assembly cavity is a wall cavity.
 16. The wallassembly of claim 14 wherein the wall assembly cavity is a barriercavity.
 17. The wall assembly of claim 14 further comprising a supportmember configured to support the permeable receptacle within the wallassembly cavity.
 18. The wall assembly of claim 17 wherein the supportmember is a bar attached at each end to a wall stud.
 19. The wallassembly of claim 14 further comprising a decorative cover covering thereceiver.
 20. The wall assembly of claim 14 wherein the receiver islocated near a bottom portion of the wall assembly cavity.
 21. The wallassembly of claim 14 wherein the receiver is located near a top portionof the wall assembly cavity.
 22. A moisture control apparatus forcontrolling moisture within a building comprising: a means forcontaining a desiccant; and a means for delivering the desiccant to abuilding cavity.
 23. The apparatus of claim 22 further comprising ameans for determining a moisture level within the building cavity.
 24. Amoisture control apparatus for controlling moisture within a buildingcomprising: a means for containing a desiccant; and a means foradsorbing moisture within a sealed building cavity, wherein the moistureis voided from lumber forming the building cavity.
 25. A moisturecontrol apparatus for controlling moisture within a building comprising:a first strip means for adsorbing moisture from a first wall cavity; asecond strip means for adsorbing moisture from a second wall cavity; anda receiver means for receiving desiccant within the first and the secondwall cavities.